diff --git a/tests/unit/script/functions/test_array_functions.py b/tests/unit/script/functions/test_array_functions.py
index bfee05da..556e77bf 100644
--- a/tests/unit/script/functions/test_array_functions.py
+++ b/tests/unit/script/functions/test_array_functions.py
@@ -62,6 +62,28 @@ class TestArrayFunctions:
         output = single_variable_output("{%array_apply(['a', 'b', 'c'], %capitalize)}")
         assert output == ["A", "B", "C"]
 
+    def test_array_apply_custom_function(self):
+        output = (
+            Script(
+                {
+                    "the_array": "{ ['a', 'B', 'c', 'D'] }",
+                    "output": "{ %array_apply(the_array, %custom_cap) }",
+                    "should_lower": "{%bool(True)}",
+                    "%custom_cap": """{
+                        %if(
+                            %bool(should_lower),
+                            %lower($0),
+                            %upper($0)
+                        )
+                    }""",
+                }
+            )
+            .resolve(update=True)
+            .get("output")
+            .native
+        )
+        assert output == ['a', 'b', 'c', 'd']
+
     def test_array_reduce(self):
         output = single_variable_output("{%array_reduce([1, 2, 3, 4], %add)}")
         assert output == 10